Field of the Invention
Embodiments of the present invention relate generally to three-dimensional (3D) printing and, more specifically, to implementing support posts for improved flexural strength in 3D-printed objects.
Description of the Related Art
A typical three-dimensional (3D) printer generates a 3D solid object based on a 3D printable digital model, such as a 3D mesh of triangles. In operation, the 3D printer creates the 3D object in layers. For instance, if the digital model were to represent a candy cane, then the 3D printer would print successive layers of material beginning with a layer corresponding to the bottom of the stem of the candy cane and ending with a layer corresponding to the top of the hook of the candy cane.
Some 3D printable digital models include sections that, when 3D-printed, are formed as tall stacks of narrow layers of 3D printable material. Intra-layer bonds are typically stronger than inter-layer bonds because of the nature of the 3D printing process and, thus, such tall stacks of narrow layers of 3D printable material are susceptible to bending forces. More specifically, during the 3D printing process, layers of a non-solidified 3D printable material, such as a gel or powder, are provided and then subsequently solidified to form the layer. Because the 3D printable material in a single layer is solidified together, the material in that layer generally forms strong intra-layer bonds. When the next layer is formed, the previous layer has already been solidified. Thus, the bonds between the next layer of 3D printable material and the previous layer are not as strong as the intra-layer bonds. Due to this aspect of 3D printing, portions of a 3D-printed object that include many stacked layers having cross-sections that are substantially narrower than the height of the stack typically have a weak flexural strength and may be damaged or destroyed during the printing process through bending.
To overcome this shortcoming, a human or computer program may analyze the 3D model to minimize the number of stacks of layers having cross-sections that are narrower than the height of the stack that are generated in the final 3D object printed from the 3D model. For example, a human or computer program may rotate the 3D model so that a section of the model that would otherwise be composed of a large number of small-profile layers when 3D-printed may instead composed of a single layer or a smaller number of thicker layers. However, such manipulation is tedious, difficult, and time consuming. Further, in some instances, such rotations of the 3D model being printed are not possible.
As the foregoing illustrates, what is needed in the art are techniques for improving flexural strength of 3D objects during printing.